Agricultural pollutants are any biotic or abiotic by-products of farming practices that lead to the contamination or the degradation of the ecosystem. Such farming practices that lead to harmful effects on humans and are detrimental to their economic interests are referred to as Agricultural pollution.
Sources of Agricultural Pollution
There are two sources of agricultural pollution, and they are the non-point source and point source pollution. Point source pollution is any single identifiable source such as water, air, noise, light, or thermal pollution. On the other hand, non-point source pollution refers to pollutants coming from many diffuse sources, for instance, pollution resulting from land runoff, precipitation, atmospheric deposition, seepage, hydrological modification or drainage, where it is difficult to trace the pollution to a single source.
Biotic Causes Of Agricultural Pollution
Biotic causes of pollution refers to living organisms which in most cases contain carbon and undergo decay. The common biotic causes of agricultural pollution include bio-pesticides, invasive species, and biological pest control among others. Bio-pesticides pollutants are pesticides that are living organisms and or natural materials such as plants, animals, bacteria, and some minerals. There are three types: Biochemical, microbial and plant-incorporated-pesticides. Bio-pesticides have a less pollution factor than traditional pesticides; they, however, have a negative impact on other (non-target) species. Invasive species may refer to foreign pests introduced accidentally and may hurt the native ecosystem once they establish themselves. An example is Centaurea solstitialis which is a foreign weed in North America that is toxic to horses and native plants. On the other hand, the use of biological pest control although safer than chemical methods have proven to be fatal in some cases. An example is when parasitoid butterflies were introduced in North American farms to control the gypsy moth, and this resulted in a devastating decline of the silk moth in the region.
Abiotic Causes Of Agricultural Pollution
Abiotic pollutants refer to non-living substances or products that affect or influence the environment and ecosystem. Some of the most common abiotic causes of pollution include pesticides, fertilizers, and heavy metals among others. Pesticides are chemical agents or products used in agricultural farms to control pests that negatively affect crop production. When used excessively they contaminate the soil thus altering the microbial process in the soil. Fertilizers, which are Nitrogen based, boost the soil’s production capacity. Only a small fraction converts to produce, however, the rest remains in the soil. Excessive fertilizers alter the soil’s PH levels and also pollute water sources. Industrial waste is also a significant pollutant introducing elements such as mercury and other heavy metals into the ecosystem.
Effects Of Agricultural Pollution
Agricultural pollution is the leading source of pollution in water bodies. When chemicals from pesticides, herbicides, and fertilizers make their way into groundwater, they end up in drinking water, and this, in turn, leads to devastating effects on health such as the blue baby syndrome. Fertilizers and manure turn into nitrate eventually which reduces the amount of oxygen in water bodies thus affecting all aquatic animals. When the concentration of toxic elements obtained from agricultural products accumulates in the soil, the soil’s fertility decreases adversely.
Controlling Agricultural Pollution
Many approaches can significantly reduce the number of agricultural pollutants in the environment. One example is applying the right amount of fertilizer at the appropriate season and in the correct way, and this will significantly reduce the amount of unconverted fertilizer that ends up in water bodies. Keeping animal waste away from water bodies will reduce the amount of nitrogen and phosphorous that end up in streams and rivers. The use of clover crops helps in recycling excess nitrogen from the soil and reduces soil erosion. Planting grass or trees around farms helps in filtering out and recycling the nutrients that end up in rivers and streams. Other control measures include conservation tillage, drainage management, and water body management.